Cita APA (7a ed.)
Orr, E. L., & Orr, W. N. (2012). Oregon geology (6th ed.). Oregon State University Press.
Cita Chicago Style (17a ed.)
Orr, Elizabeth L., y William N. Orr. Oregon Geology. 6th ed. Corvallis: Oregon State University Press, 2012.
Cita MLA (9a ed.)
Orr, Elizabeth L., y William N. Orr. Oregon Geology. 6th ed. Oregon State University Press, 2012.
Precaución: Estas citas no son 100% exactas.